Apparatus for processing garbage

ABSTRACT

Apparatus for processing garbage according to the present invention includes a conveyor belt to convey the garbage to a grinder that comminutes the raw garbage. A hopper receives the comminuted raw garbage from the grinder and supplies it to feed screws feeding the raw comminuted garbage onto heated metal platens that compress and dry the garbage. A scraper is provided for removing adhered garbage from the platens, and a second hopper is disposed to receive the compressed and dried garbage scraped from the metal platens and to deposit it into a second grinder where it is comminuted for final disposition in containers.

. C Umted States Paten [191 1111 3,871,291 Lassiter Mar. 18, 1975 [54] APPARATUS FOR PROCESSING GARBAGE 1,210,408 l/i917 Brockhausen 99/483 X 1 inventor Rush Lassiter. Hammond, 313333213 11/132; 15 55215251711: 111.??1331132 73 A Fl d R h C B t 3,478,192 11/1969 Fink..... 219/243 1 ss'gnee gi a on 3,651,755 3/1972 Gati 100/98 R [22] Fiied: 1973 Primary Examin'erPeter Feldman [2]] Appl. No.: 348,616

Related US. Application Data [57] ABSTRACT [62] Division of Ser. No. 213,378, Dec. 29, 1971, Apparatus f processing b according to the abandoned' present invention includes a conveyor belt to convey the garbage to a grinder that comminutes the raw gar- [52 U.S. c1. 100/93 P, 100/38, 100/39, bage A hopper receives the comminuted raw garbage loo/96 loo/l 23/2591 24l/23 34/14 from the grinder and supplies it to feed screws feeding [51] 'f Bozc 11/08 1330b 9/00 1330b 13/00 the raw comminuted garbage onto heated metal plat- [58] Field of Search 23/2593, 259.1; 219/243, ens that Compress d d y the garbage. A scraper is 219/9498 93 39; 99/484 provided for removing adhered garbage from the plat- 646; 241/23; 34/12 60; 426/335 ens, and a second hopper is disposed to receive the compressed and dried garbage scraped from the metal [56] References C'ted platens and to deposit it into a second grinder where it UNITED STATES PATENTS is comminuted forfinal disposition in containers. 603,945 5/1898 Edgerton 100/38 X 994,047 5/1911 Wiselogel 23 2593 19 Clalms, 7 Drawmg Figures FATENTEfl 1% sum 2 or 3 1 I APPARATUS FOR PROCESSING GARBAGE This application is a divisional of application Ser. No. 213,378 filed Dec. 29, 1971, now abandoned.

BACKGROUND OF THE INVENTION This invention relates to an improved apparatus for comminuting and drying various types of garbage and refuse. More particularly, the invention relates toan improved apparatus for comminuting and drying garbage composed primarily of food waste produced by dining establishments such as restaurants, cafeterias, and the like.

U.S. Pat. No. 1,101,129, issued June 23, 1914, U.S. Pat. N. 1,493,335, issued May 6, 1924, and U.S. Pat. No. 2,089,978, issued Aug. 17, 1937, disclose various processes and apparatus for treating and handling material such as garbage. U.S. Pat. No. 1,493,335 discloses a process whereby garbage is dried by pressing the garbage between a roller and the surface of a heated plate, thereby accomplishing heating and disintegration simultaneously. U.S. Pat. No. 1,101,129 teaches drying garbage by heating the garbage in an oven. U.S. Pat. No. 2,089,978 teaches drying the garbage by passing it on a conveyor through an oven.

Garbage discarded from dining establishments contains a high degree of nutrients since such garbage is primarily food waste. Such garbage is typically discarded by burning or dumping in a refuse dump. No benefit is usually realized from the various nutrients contained in the garbage.

It is an object of the present invention to provide apparatus for grinding and drying garbage.

It is another object of the present invention to provide apparatus for grinding and drying food waste.

It is still another object of the present invention to provide apparatus for producing fertilizer and animal food from disposed food.

The present invention provides apparatus forgrinding and drying disposed foO d garbage and for processing the garbage into a comminuted material that may be used for fertilizer or for animal or poultry feed. The apparatus utilized in processing the garbage includes conveyor means for transporting unprocessed or raw garbage to the processing apparatus and comminuting the same to render it suitable for subsequent drying. Apparatus is also utilized to convey the comminuted raw garbage from the grinding apparatus to an upper and lower heated platen assembly and to deposit it in relatively thin layer form on the lower platen. The heated platens are then moved together, compressing and causing heating of the garbage layer. The pressure created by the platens on the garbage layer may be varied during the heating and compression process if desired or it may be continuously varied during the heating process depending upon the character of the garbage being processed or upon the results intended. After the garbage layer or layers have been suitably dried, the platens are moved apart and the garbage is removed in any suitable manner. The dried garbage then is comminutcd and placed into containers for ultimate disposal.

BRIEF DESCRIPTION OF THE DRAWINGS So that the manner in which the recited features,'advantages and objects of the present invention as well as others, which will become apparent, are obtained and can be understood in detail, more particular description of the invention briefly summarized above may be had by reference to the embodiment thereof which is illustrated in the appended drawings, which drawings form a part of this specification.

It is to be noted, however, that the appended drawings Llustrate only a single representative embodiment of this inventioiiand such embodTment isno t tobe can sidered limiting of the scope of the invention, for the invention may admit to other equally effective embodimentswithout departing from the spirit and the scope hereof. In the Drawings: FIG. 1 is a side elevational view of the garbage processing system of the present invention;

FIG. 2 is an exploded perspective view of grinding blades utilized in the grinding apparatus;

FIG. 3 is a front elevational view of the garbage processing system of the present invention;

- FIG. 4 is a fragmentary sectional view of FIG. 3

taken along lines 4-4;

FIG. 5 is a'fragmentary sectional view of FIG. 3 taken along lines 5-5;

FIG. 6 is a fragmentary elevational view of the scraper structure of FIG. 1 showing the operation of the refuse scraper; and

FIG. 7 is a perspective view of the apparatus for feeding garbage to the heated metal plates and having part thereof broken away and illustrating the raw garbage feed mechanism in detail.

DESCRIPTION OF THE PREFERRED EMBODMIMENT Referring now to the drawings, in FIG. 1 is shown garbage container 10 which holds the raw garbage to be processed. The raw garbage is classified residual food prod uct garbage from which most non-food product garbage has been remdvai'cbn'faiiiritj'fiiaybe a hopper or any other mechanism that provides raw garbage at an optimum quantity rate for efficient comminution. The raw garbage 11 is poured from container 10 onto endless conveyor belt 12 which revolves on rollers 13. The raw garbage travels along conveyor belt 12 beneath a metal scanner 14 which detects any ferrous or non-ferrous metal in the garbage and stops conveyor belt 12 by actuating an electrical relay or by any other conventional means. The metal thus detected may be removed manually in the case of non-ferrous metal or by a magnet devise if ferrous metal is detected. Any other metal removal mechanism may be employed within the spirit and scope of the present invention. Metal scanner 14 can be any conventional metalscanning device known in the art such as those used in airports to detect metal objects that might be carried by airline passengers boarding an aircraft.

The garbage 11 is dumped from conveyor belt 12 into an upper hopper 15 between anvil 17 and anvil 18 where it is contacted by an upper grinder 20.

Food waste type garbage frequently contains small quantities of non-food material such as various plastic wrapping materials, paper, wood, glass, string, bone and the like. Grinding mechanisms capable of properly grinding most food wastes are incapable of properly comminuting such non-food materials. The grinding mechanism of the present invention is particularly designed to achieve proper grinding or comminuting of both food wastes and mast'aba ;fia1"maeaa thatis of non-food character.

It is very important that upper grinder 20 be capable of grinding the raw garbage into fine particles for rapid drying. Upper grinder 20 may be any conventional grinder well known in the art that is suitable for comminuting both food waste and the non-food materials or dinarily accumulated with food 'wasts. It is preferred, however, that a grinder as shown in FIG. 2 be employed. The grinder shown in FIG. 2 has a series of blades 21 mounted on a splined shaft 23 and spaced apart by spacers 24.

Upper grinder 20 and lower grinder 62, shown in FIGS. 1 and 2, may be identical. FIG. 5 shows a partly sectional view of grinder 62 in which blades 21 can be seen to rotate within slots 16 in cutting anvil l7. Anvil 18, as seen in FIG. 4, is similar in design to anvil 17 and has slots (not shown) for receiving blades 21. The blades 21 are preferably two trapezoids spaced 180 apart, as can be seen in FIG. 2. The angle a of the sides of the trapezoidal blade may vary from about 0 to about 90. Preferably the angle varies from about 30 to about 60 to achieve optimum comminution of both food waste and non-food waste material of the character described above. The angle between the center lines of each successive blade may vary from about to about 90, or more preferably from about 45 to about 90. An angle of 60 is most preferred.

The grinder may be driven by an electric motor 22, as indicated in. FIG. 3. After passing through the grinder the garbage falls down through the bottom of top hopper l5 and into flexible conduit 25 and is conducted by the conduit into hopper 26. As can be seen in FIG. 7, the flexible conduit 25 is attached to the top 27 of hopper 26 which prevents excess garbage from overflowing from the hopper.

The garbage falls downward into feed tubes 28, as seen in FIG. 7, and onto feed screws 29 contained in feed tubes. The feed tubes 28 are supported by a rolling table 41 having wheels 39 that are received by a track 40. Movement of the reciprocating table 41 along track 40 is controlled by a piston rod 30 connected to a piston located in cylinder 31. Cylinder 31 may be any conventional hydraulic or pneumatic cylinder well known in the art.

Feed screws 29 have shafts 37 extending from feed tubes 28 upon which a bevel gear 36 is mounted. Bevel gear 36 contacts bevel gear 42 which is aligned perpendicularly thereto. At each end of shaft 43 is disposed a pinion gear wh ich engages rack 38. A one w'ay clutch (not shown) connects gear 35 to shaft 43. The one-way clutch allows shaft 43 to turn only when table 41 is moving away from lower heating plate 45. Such clutches are well known in the art and any conventional one-way clutch may be used. Therefore, feed screws 29 turn only when table 41 is moving away from plate 45.

To deposit garbage on the lower heating platen 45, rod 30 forces table 41 forward toward the lower heating plate or platen 45, as indicated in FIG. 1. After table 41 is fully driven toward lower heating plate 45, as indicated by the dotted lines in FIG. 1, rod 30 begins to retract and gear 35 begins to turn in a counterclockwise direction. The one-way clutch connecting gear 35 to drive shaft 43 is actuated and therefore shaft 43 is also rotated counterclockwise to drive feed screws 41. As feed screws 41 turn garbage is forced out of feed tubes 28 onto hot plate 45 in broad layers of relatively even thickness. Comminuted garbage 11 is shown deposited on lower heating plate 45 in FIG. 7.

After table 41 has been fully withdrawn and a full charge of garbage 11 has been deposited on lower heating plate 45, upper heating plate or platen 46 is moved downward into contact with garbage 11 by piston rod 48 which may be identical to piston rod 30. Upper heating plate 46 is guided down by guides 50. Conduits 47, shown in FIGS. 3'and 7, attached to upper heating plate 46 and lower heating plate 45 contain electrical wiring for electrically heating the plates. The pressure on the garbage held between the two heating plates can be regulated by regulating the force applied to the piston rod 48 by the piston.

Depending upon the results intended, the heated platens may be brought into contact with the layer of comminuted garbage and a speciflc pressure may be maintained upon the garbage during the heating and drying cycle. If desired the platens may exert light or heavy pressure upon the comminuted garbage during the initial phase of the heating and drying process and the pressure may be increased or reduced in steps during other phases of the drying process. It may be appropriate to continuously vary the mechanical pressure applied by the platens to the garbage layer during the heating and drying process if such renders the product produced more acceptable for the intended use or if the garbage may be dried in a shorter period of time by employing such variations.

After the two heating plates have been in contact with the garbage for a period of time sufficient to dry the layers of comminuted garbage, the upper heating plate is withdrawn by rod 48. A scraper 51, as shown in FIG, 6, may then be forced across lower heating plate 45 to scrape the dry, compressed garbage 11 from the lower heating plate. Scraper 51 is any conventional plate or scraperwhich will contact lower heating plate 45 and upper heating plate 46 when forced between the plates to remove garbage adhering to both plates 45 and 46. The scraper 51 is actuated by piston rod 49 which may be identical to rod 30. Plates 45 and 46 preferably have tapered edges (not shown) located on the side facing scraper 51 to enable scraper 51 to slide easily between the plates.

The dried garbage 11 scraped from heating plates 45 and 46 falls into upper garbage chute 54 and then gravitates from chute 54 into a rotatable receiving bin 55 through receiving bin opening 56. Receiving bin 55 is rotated by an electric motor 57 to deposit the garbage into lower chute 60. Lower chute 60 guides the garbage into lower hopper 61 which may be substantially identical in design to upper hopper 15 and contains a grinder that may, if desired, be substantially identical to upper grinder 20.

After the dried garbage is ground it gravitates through the grinder onto closing device or valve 63. g lnas may be u s s c sd. driqs saisia t a a by circulating drying air through the pulverant material. It is important to achieve drying of the material before it loses the heat applied during initial compression and drying to achieve efficient drying. Motor 66 may if desired be a combination motor and blower and may transport drying air into the grinding chamber to achieve final drying. Closing device 63 may consist of a flat plate or gate which can be moved laterally to open and close the bottom of hopper 61, or may be any other conventional hopper closing device. When the bottom of hopper 61 is opened the processed garbage falls into bag 65 held by bag stand 64. The bag may then be sealed and removed.

lnpracticing the process of the present invention it is important that the temperature of lower heating plate means comprises a scraper connected to a piston rod, said piston rod being aligned parallel to said upper and said lower hot platens means, said scraper being positioned to contact both interior surfaces of said upper platen means comprises a flat plate containing electrical wiring for heating said plate.

4. The apparatus of claim 1 wherein said scraper 45 and upper heating plate 46 be. maintained within a -5 hot platen and said lower hot platen to scrape said gartemperature range of from about 2 l 2F to about 900F. bage therefrom. Upper Plate 46 ShQuld be agamst the garbage for 5. The apparatus of claim 4 wherein said upper hot about 20 seconds to about 3 minutes, or more preferaplaten and said lower hot platen have tapered edge y f about 1 to 3 mlnutes- Preferably the means located on the sides of said platens adjacent said he g Plates are malmalned at a temperature of from scraper means to facilitate receipt of said scraper beabout 300F to about 600F,,or more preferably from tween Said platens about 400F to about 550F. The pressure applied on 6 The a t f l l h f d the garbage'by the heating plates 45 and 46 ranges P Z g c alm W a means from about 20 to about 1000 pounds per square foot. :s ggg 66 m 6 means containing ee screw The pressure on the garbage may be applied by lowering upper plate 46 at a continuous rate or upper 7. The apparatus of cla m 6 wherem saidfeed tube plate 46 may be lowered stages preferably upper means s generally cylindrlcal in shape and 15 adapted plate 46 is lowered until it barely touches the garbage receflve 851d garbageand exerts no pressure thereon and is left in this posi- 8- The app r us 'of claim 7 wherein said feed screw tion for a few seconds. Then upper plate 46 may be means comprises a rotatable screw. lowereduntilapressu re of 20 pounds per square foot is 9. An apparatus for drying and compressing garbage, achieved and left in this position for a period of time. comprising: Further increases in pressure may be made as desired.

In all of the following examples the upper and lower g g means for grinding Said garbage, heating plates were maintained at a temperature of lower hOt pl means, about 300F, the force on the garbage was about 550, upper hot platen means, means for moving at least and the total amount of time the garbage was held beone of said upper and lower hot platen means totween the two heating plates was 1 minute. ward and away from the other of said hot platen The processed garbage was analyzed with the followmeans, 7 ing results: v feed means for placing garbage on said lower hot Sample Processed Garbage pH Moisture Ash Ca P N K 1 Dark 5.7 7.25 7.44 0.37 0.20 1.42 0.13 2 Medium 5.5 7.74 7.20 0.37 0.22 1.53 0.13 3 Light 4.9 8.51 4.3l 0.25 0.23 2.22 0.2l

As can be seen from the foregoing examples, the proplaten means, cessedgarbage is high in various mineral content which conduit means connecting said grinding means to makes it suitable for use as a fertilizer or as animal and 40 said feed means, and poultry feed. scraper means for scraping garbage from said upper The foregoing is considered as illustrative only of the and said lower hot platen means. principles of the invention, Further, since numerous 10, Th apparatus f l i 9 wh i e h f s id modifications or changes will readily occur to those lower b t l t n means a d id upper hot l ten in the art, lS 110i desired to the invention means each comprise a flat plate Containing electrical to the exact construction and operation shown and dei i g for heating said plates. scribed, and accordingly all suitable modifications and 11 h apparatus f l i 10 h i i Scraper equivalents y be resorted falling within the Scope means comprises a scraper connected to a piston rod, of invention as Claimedsaid piston rod being aligned parallel to said upper and what is Claimed is: said lower hot platens, said scraper being positioned to 1 A apparatus f d i d compressing -b contact both interior surfaces of said upper hot platen i i and said lower hot platen to scrape garbage therefrom. lower hot platen means, 12. The apparatus of claim 9 wherein said feed means upper hot platen means, means for moving said upper comprises feed tube means containing feed 'screw and lower hot platen means toward and away from means, said feed tube means being generally cylindrical one another, in shape and adapted to receive said garbage, said feed feed means for placing garbage on said lower hot screw means comprising a rotatable screw.

platen, and 13. The apparatus of claim 1 2 wherein said feed tube 1 Scraper means for p g g g m Said lower means is connected to rolling tibia means, said rolling hot plate means and said upper hot platen means. table means being adapted to roll said feed tube means 2. The apparatus of claim 1 wherein said lower hot between said upper hot platen means and said lower platen means comprises a flat plate containing electrihot platen means. cal wiring for heating said plate. 14. The apparatus of claim 13 wherein said feed 3. The apparatus of claim lwherein said upper hot means contains means for turning said feed screw means to deposit garbage on said lower hot platen means as said feed tube means is drawn over said upper hot platen means and said lower hot platen means.

17. The apparatus of claim 16 wherein said apparatus includes metal detection means located sufficiently close to said conveyor belt means to detect any metal present in said garbage.

18. The apparatus of claim 9 wherein said apparatus includes second grinding means for grinding garbage scraped from said hot platens.

19. The apparatus of claim 9 wherein said apparatus includes means for placing said garbage in containers. 

1. An apparatus for drying and compressing garbage, comprising: lower hot platen means, upper hot platen means, means for moving said upper and lower hot platen means toward and away from one another, feed means for placing garbage on said lower hot platen, and scraper means for scraping garbage from said lower hot plate means and said upper hot platen means.
 2. The apparatus of claim 1 wherein said lower hot platen means comprises a flat plate containing electrical wiring for heating said plate.
 3. The apparatus of claim 1 wherein said upper hot platen means comprises a flat plate containing electrical wiring for heating said plate.
 4. The apparatus of claim 1 wherein said scraper means comprises a scraper connected to a piston rod, said piston rod being aligned parallel to said upper and said lower hot platens means, said scraper being positioned to contact both interior surfaces of said upper hot platen and said lower hot platen to scrape said garbage therefrom.
 5. The apparatus of claim 4 wherein said upper hot platen and said lower hot platen have tapered edge means located on the sides of said platens adjacent said scraper means to facilitate receipt of said scraper between said platens.
 6. The apparatus of claim 1 wherein said feed means comprises feed tube means containing feed screw means.
 7. The apparatus of claim 6 wherein said feed tube means is generally cylindrical in shape and is adapted to receive said garbage.
 8. The apparatus of claim 7 wherein said feed screw means comprises a rotatable screw.
 9. An apparatus for drying and compressing garbage, comprising: grinding means for grinding said garbage, lower hot platen means, upper hot platen means, means for moving at least one of said upper and lower hot platen means toward and away from the other of said hot platen means, feed means for placing garbage on said lower hot platen means, conduit means connecting said grinding means to said feed means, and scraper means for scraping garbage from said upper and said lower hot platen means.
 10. The apparatus of claim 9 wherein each of said lower hot platen means and said upper hot platen means each comprise a flat plate containing electrical wiring for heating said plates.
 11. The apparatus Of claim 10 wherein said scraper means comprises a scraper connected to a piston rod, said piston rod being aligned parallel to said upper and said lower hot platens, said scraper being positioned to contact both interior surfaces of said upper hot platen and said lower hot platen to scrape garbage therefrom.
 12. The apparatus of claim 9 wherein said feed means comprises feed tube means containing feed screw means, said feed tube means being generally cylindrical in shape and adapted to receive said garbage, said feed screw means comprising a rotatable screw.
 13. The appartus of claim 12 wherein said feed tube means is connected to rolling table means, said rolling table means being adapted to roll said feed tube means between said upper hot platen means and said lower hot platen means.
 14. The apparatus of claim 13 wherein said feed means contains means for turning said feed screw means to deposit garbage on said lower hot platen means as said feed tube means is drawn over said upper hot platen means and said lower hot platen means.
 15. The apparatus of claim 9 wherein said grinding means being generally in the shape of two trapezoids spaced 180* apart, the edge of said trapezoids forming an angle with the centerline of said trapezoids between 0* and 90*, the angle between the centerline of each successive blade of said grinder varying from about 20* to about 90*.
 16. The apparatus of claim 9 wherein said apparatus includes conveyor belt means for conveying garbage to said grinder.
 17. The apparatus of claim 16 wherein said apparatus includes metal detection means located sufficiently close to said conveyor belt means to detect any metal present in said garbage.
 18. The apparatus of claim 9 wherein said apparatus includes second grinding means for grinding garbage scraped from said hot platens.
 19. The apparatus of claim 9 wherein said apparatus includes means for placing said garbage in containers. 